Biomedical subjects

Megan A Pattison

Publications and source records attributed to Megan A Pattison.

3 recordsLinked to original sources

PubMed2006

Select bladder smooth muscle cell functions were enhanced on three-dimensional, nano-structured poly(ether urethane) scaffolds.

Bladder wall resection is often required as a treatment for invasive bladder cancer. When this happens, a suitable replacement material is needed. The present study, therefore, created three-dimensional, porous, nano-structured poly(ether urethane) (PU) matrices for use as bladder tissue-engineering scaffolds. Select cytocompatibility experiments (specifically adhesion and long-term growth studies) were performed on these scaffolds using human bladder smooth muscle cells (BdSMCs). In addition, the amount of total collagen and elastin present in each cell-seeded scaffold was determined since the production of these extracellular matrix (ECM) proteins is essential for the health and survival of cells and for the functionality of the replaced organ. Finally, to better understand how these scaffolds and resident cells would perform in the complex mechanical environment of the bladder wall, scaffolds and cells were subjected to 10 cmH2O pressure using a computer-controlled pressure chamber. Results provided evidence that compared to conventionally used, micro-dimensional PU scaffolds, the novel, nanodimensional scaffolds created in this research increased cell adhesion, growth, and ECM protein production. Additionally, scaffolds and resident cells were not affected by exposure to 10 cmH2O pressure (compared to controls maintained under atmospheric conditions). These results are promising and provide evidence that the nano-dimensional PU scaffolds created in this research are suitable bladder replacement materials that may outperform materials currently used for such purposes.

Animals↗

PubMed2005

Three-dimensional, nano-structured PLGA scaffolds for bladder tissue replacement applications.

In total, approximately 400 million people worldwide suffer from urinary bladder cancer (Nat Biotechnol 17 (1999) 149). When radical cysectomy is required as treatment, a replacement material is clearly necessitated. For this purpose, three-dimensional poly(lactic-co-glycolic acid) (PLGA) scaffolds were constructed using solvent casting and salt leaching processes. These scaffolds were manipulated to possess nano-dimensional surface features by soaking in sodium hydroxide at select concentrations and for various periods of time. Human bladder smooth muscle cells were then seeded onto these nano-dimensional scaffolds; adhesion and longer-term cell growth experiments were performed for either 4 h, or 1, 3, and 5 days, respectively. Additionally, collagen and elastin production was quantified following each experiment. In all cases, control cells were placed in an incubator and subjected to normal atmospheric pressure, while experimental cells were placed in a pressure chamber and subjected to a sustained pressure of 10 cm H(2)O. Results of this study provided evidence that porous, nano-dimensional polymeric scaffolds enhanced cell adhesion and growth, while also promoting increased elastin and collagen production. Moreover, in general, exposure to pressure did not alter cellular adhesion, growth, or extracellular matrix protein production, which suggests that the scaffolds and their resident cells will fair well in the complex mechanical environment of the bladder wall. In combination, these results provide evidence that the nano-dimensional PLGA scaffolds created in this research are promising as the next generation of bladder wall replacement materials.

Biocompatible Materials↗

PubMed2005

Accelerated chondrocyte functions on NaOH-treated PLGA scaffolds.

Compared to conventional poly(lactic-co-glycolic acid) (PLGA), previous studies have shown that NaOH-treated PLGA two-dimensional substrates enhanced functions of osteoblasts (bone-forming cells), vascular and bladder smooth muscle cells, and chondrocytes (cartilage-synthesizing cells). In this same spirit, the purpose of this in vitro study was to fabricate three-dimensional NaOH-treated PLGA scaffolds and determine their efficacy toward articular cartilage applications. To improve functions of chondrocytes including their adhesion, growth, differentiation, and extracellular matrix synthesis, PLGA scaffolds were modified via chemical etching techniques using 1N NaOH for 10 min. Results demonstrated that NaOH-treated PLGA three-dimensional scaffolds enhanced chondrocyte functions compared to non-treated scaffolds. Specifically, chondrocyte numbers, total intracellular protein content, and the amount of extracellular matrix components (such as glycosaminoglycans and collagens) were significantly greater on NaOH-treated than on non-treated PLGA scaffolds. Underlying material properties that may have enhanced chondrocyte functions include a more hydrophilic surface (due to hydrolytic degradation of PLGA by NaOH), increased surface area, altered porosity (both percent and diameter of individual pores), and a greater degree of nanometer roughness. For these reasons, this study adds a novel tissue-engineering scaffold to the cartilage biomaterial community: NaOH-treated PLGA. Clearly, such modifications to PLGA may ultimately enhance the efficacy of tissue-engineering scaffolds for articular cartilage repair.

Biocompatible Materials↗